My grandmother used to say she could tell how a person was feeling by what their stomach was doing, and I always thought that was just something older people said. Then I read that the phrase ‘gut feeling’ has picked up a far more literal meaning in recent years, and I had to sit with that for a bit over my morning tea.
Neuroscience and medical research keep circling back to one idea: our brain and our gut are in close, constant conversation. It runs both ways. The state of the gut seems to reach up and touch the brain, and the mood of the brain seems to reach down and stir the gut. With something like 100 trillion microbes living down there, that is an enormous amount of chatter going on while we get on with our day.
I first came across this through Dr Nicola Gates, a Sydney clinical psychologist who has written on brain health and speaks about it in a way that finally made the science stick for me. What follows is my own reading of it, from my kitchen and my walks along the water, not a clinic.
The two-way street between your belly and your head
The friendly residents in our gut are naturally occurring bacteria that together make up what scientists call the commensal intestinal microbiome. They have been part of the human story for as long as there have been humans, and we have been part of theirs. It is less a case of us hosting them and more a case of an old partnership.
Think of the language we already use without thinking. A ‘gut feeling’ about a decision. ‘Butterflies’ before something nerve-racking. Something being ‘gut wrenching’ when it is genuinely awful. Every one of those phrases quietly admits that what happens in the mind shows up in the belly. Dr Gates describes this as the brain-gut axis, and the traffic on it never really stops.
What that means, if the researchers are reading it right, is that neglecting those tiny residents can tilt things the wrong way. Too few of the helpful types, too many of the unhelpful ones, and the flow-on effects that get mentioned range from more allergies and lower immunity to higher inflammation. I am not going to pretend I understand the mechanics in full, but the broad picture is one I can act on at the level of an ordinary shopping list.
What I try to feed the good residents
Here is the part I can actually do something about. A varied diet built around fresh fruit and vegetables gives the good microbes the raw material they need, sometimes called prebiotics, the food that feeds the helpful bacteria. When I plan a week of meals now, I aim for range rather than perfection: different colours, different plants, a rotating cast rather than the same three vegetables on repeat.
- A spread of vegetables across the week instead of the usual suspects
- Fruit eaten whole, skin and all where it makes sense
- Whole grains and legumes doing more of the heavy lifting
- Fermented bits and pieces where I enjoy them, more for pleasure than prescription
On the other side of the ledger, Dr Gates talks about the ‘white toxins’ worth reining in: salt, sugar, processed flour, and the poorer omega-6 fats. I do not treat these as forbidden, because that road never lasts for me. I just let them take up less room. If you are rethinking your plate more broadly, our notes on nailing nutrition and the gut health challenge are a gentler place to begin than any strict overhaul.
Why a settled gut might matter to a clear head
When the good populations are looked after, the theory goes that the troublesome bacteria have less room to move. Researchers link a well-tended microbiome to steadier inflammation levels and a calmer stress response, and to the ongoing production of neurotrophins, which behave a little like fertiliser for the brain and help it stay adaptable. Put plainly, the idea is that a content gut gives the brain room to grow and settle.
I want to be careful here, because I am a wellness writer and not a clinician. None of this is a treatment plan. For anything you are genuinely worried about, the general information at Healthdirect is a sound starting point, and a chat with your GP or a dietitian beats anything you will read online, mine included.
The mind half of the equation
What struck me most in Dr Gates’ work is that diet is only half the story. Because the conversation runs both ways, the state of our mind pushes back on the gut just as firmly as food does. Prolonged stress, the low simmer of anxiety, poor sleep, all of it seems to register down below.
So the boring, unglamorous habits earn their keep. Reducing stress where you can. Making room for real rest. A bit of meditation or mindfulness, even ten quiet minutes. I am biased, because my own version of this is an early ocean swim on the Central Coast followed by ten minutes with a journal, and I would defend that ritual against almost anything on my calendar. Betterhealth Victoria has some plain-spoken wellbeing pages if you want somewhere sensible to poke around.
Sleep, in particular, gets short shrift in the wellness conversation, and I think that is a mistake. When I sleep badly my appetite for the very foods I have been talking about drops off a cliff, and I reach for the salty, sugary, easy things instead. If that pattern sounds familiar, our thoughts on sleep and weight loss come at the same problem from a kinder angle.
Small habits that stack up
None of this needs to be a project. I have found the changes that stick are the small, slightly dull ones repeated often. A better breakfast. A walk after dinner. Fewer late scrolls, more early nights. If you like the idea of feeding your mood through your plate, our piece on calming foods pairs nicely with the same thinking, and a slow cup of honey and lemon tea is my own excuse to sit down and do nothing for five minutes.
A content gut and a steady mind seem to keep each other company. Look after one and you are quietly looking after the other.
Where I would start this week
If I were beginning again, I would not chase perfection. I would add one extra vegetable a day, take the pressure off dinner, protect my sleep, and give myself a genuine pause somewhere in the afternoon. My grandmother may not have had the science, but she had the instinct, and the instinct turns out to hold up rather well.
— Tanya Pryce, Golden Door Living
